Home/Chain Registry/Block #199,559

Block #199,559

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 10/8/2013, 11:06:22 AM · Difficulty 9.8878 · 6,595,235 confirmations

TWN
Bi-Twin Chain

Interleaved pairs of primes that differ by 2, forming twin prime pairs at each level.

Block Header
Block Hash
8bb2198269025aa7c5691090219ba758110939a43424f2d4a3607746d56da4e4

Height

#199,559

Difficulty

9.887790

Transactions

7

Size

2.23 KB

Version

2

Bits

09e3463b

Nonce

9,005

Timestamp

10/8/2013, 11:06:22 AM

Confirmations

6,595,235

Merkle Root

38a766c23328c493e050faeb4c63015bdd866d3cb68955e6c42a54b5ce943e04
Prime Chain Origin

This is the prime chain origin stored in the block header. It is a composite number (not prime itself) — it equals the first prime in the chain multiplied by a primorial. The origin anchors the entire chain to this specific block.

6.590 × 10⁹⁴(95-digit number)
65901455851285078823…47132090222642744320
Discovered Prime Numbers
Lower: 2^k × origin − 1 | Upper: 2^k × origin + 1

These are the actual prime numbers discovered by this block, computed using the verified Primecoin formula. Each number has been independently confirmed to pass the Fermat primality test. Use the FactorDB links to verify any number independently.

Level 0 — Twin Prime Pair (origin ± 1)
origin − 1
6.590 × 10⁹⁴(95-digit number)
65901455851285078823…47132090222642744319
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
6.590 × 10⁹⁴(95-digit number)
65901455851285078823…47132090222642744321
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: origin + 1 − origin − 1 = 2 (twin primes ✓)
Level 1 — Twin Prime Pair (2^1 × origin ± 1)
2^1 × origin − 1
1.318 × 10⁹⁵(96-digit number)
13180291170257015764…94264180445285488639
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.318 × 10⁹⁵(96-digit number)
13180291170257015764…94264180445285488641
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^1 × origin + 1 − 2^1 × origin − 1 = 2 (twin primes ✓)
Level 2 — Twin Prime Pair (2^2 × origin ± 1)
2^2 × origin − 1
2.636 × 10⁹⁵(96-digit number)
26360582340514031529…88528360890570977279
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.636 × 10⁹⁵(96-digit number)
26360582340514031529…88528360890570977281
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^2 × origin + 1 − 2^2 × origin − 1 = 2 (twin primes ✓)
Level 3 — Twin Prime Pair (2^3 × origin ± 1)
2^3 × origin − 1
5.272 × 10⁹⁵(96-digit number)
52721164681028063058…77056721781141954559
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
5.272 × 10⁹⁵(96-digit number)
52721164681028063058…77056721781141954561
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^3 × origin + 1 − 2^3 × origin − 1 = 2 (twin primes ✓)
Level 4 — Twin Prime Pair (2^4 × origin ± 1)
2^4 × origin − 1
1.054 × 10⁹⁶(97-digit number)
10544232936205612611…54113443562283909119
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 consecutive prime numbers forming a Bi-Twin Chain. The prime chain origin — the large number shown above — anchors the chain and is divisible by a primorial (the product of small primes), cryptographically tying these prime numbers to this specific block.

View full Prime Chain Discovery page →
★☆☆☆☆
Rarity
CommonChain length 9
How Primecoin's Proof-of-Work Constructs These Primes

Primecoin stores a value called the prime chain origin in each block. The miner found a large integer such that when divided by a primorial (the product of small primes: 2 × 3 × 5 × 7 × …), the result is the first prime in the chain. The origin is deliberately divisible by this primorial — that divisibility is part of the proof.

Prime Chain Origin = First Prime × Primorial (2·3·5·7·11·…)
Source: Primecoin prime.cpp — CheckPrimeProofOfWork()

This is why the origin has many small prime factors — those factors are the primorial divisor. The chain then extends from the first prime using the TWN formula:

TWN: twin pairs (p, p+2) where p = origin/primorial − 1 and p+2 = origin/primorial + 1
Verify on a Primecoin Node

Anyone running a Primecoin node can independently verify this block using the following RPC commands. Run these from the primecoin-cli command line or via the debug console in the Primecoin wallet.

1. Get block hash by height
getblockhash 199559

Returns the block hash for a given block height. Use this to confirm the hash shown above matches the chain.

2. Get full block data
getblock 8bb2198269025aa7c5691090219ba758110939a43424f2d4a3607746d56da4e4

Returns the full block header including difficulty, prime chain origin, prime chain type, transaction IDs, and all other fields shown on this page.

How to run these commands: To verify this data independently, open a terminal on your own Primecoin node and run primecoin-cli <command>. Alternatively, open the Primecoin-Qt wallet, go to Help → Debug Window → Console, and type the command directly. The node must be fully synced to this block height for the commands to return results.

Cross-reference on Chainz Explorer

Chainz is an independent Primecoin block explorer. Compare this block's data to verify accuracy.

View Block #199,559 on Chainz ↗
Circulating Supply:57,602,406 XPM·at block #6,794,793 · updates every 60s
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